There are too many state-owned enterprises in France, including arms enterprises, aircraft manufacturing and railways. For example, railway electricity, gas and postal services are all state-controlled shares. You can search online. I know a few for your reference.
French banks, credit lyonnais, General Bank and many insurance companies.
Peugeot Citroen Group
Renault automobile company of France
French post
French natural gas company
Air France
France Telecom (France Telecom)
French public transport company (RATP)